diff options
Diffstat (limited to 'gcc/tree-ssa-phiopt.c')
| -rw-r--r-- | gcc/tree-ssa-phiopt.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/gcc/tree-ssa-phiopt.c b/gcc/tree-ssa-phiopt.c index ab63bf6..8b60ee8 100644 --- a/gcc/tree-ssa-phiopt.c +++ b/gcc/tree-ssa-phiopt.c @@ -51,6 +51,7 @@ along with GCC; see the file COPYING3. If not see #include "internal-fn.h" #include "gimple-range.h" #include "gimple-match.h" +#include "dbgcnt.h" static unsigned int tree_ssa_phiopt_worker (bool, bool, bool); static bool two_value_replacement (basic_block, basic_block, edge, gphi *, @@ -390,7 +391,7 @@ replace_phi_edge_with_variable (basic_block cond_block, gimple_stmt_iterator gsi; tree phi_result = PHI_RESULT (phi); - /* Duplicate range info if we're the only things setting the target PHI. + /* Duplicate range info if they are the only things setting the target PHI. This is needed as later on, the new_tree will be replacing The assignement of the PHI. For an example: @@ -398,19 +399,22 @@ replace_phi_edge_with_variable (basic_block cond_block, _4 = min<a_1, 255> goto bb2 - range<-INF,255> + # RANGE [-INF, 255] a_3 = PHI<_4(1)> bb3: use(a_3) - And _4 gets prograted into the use of a_3 and losing the range info. - This can't be done for more than 2 incoming edges as the progration - won't happen. */ + And _4 gets propagated into the use of a_3 and losing the range info. + This can't be done for more than 2 incoming edges as the propagation + won't happen. + The new_tree needs to be defined in the same basic block as the conditional. */ if (TREE_CODE (new_tree) == SSA_NAME && EDGE_COUNT (gimple_bb (phi)->preds) == 2 && INTEGRAL_TYPE_P (TREE_TYPE (phi_result)) && !SSA_NAME_RANGE_INFO (new_tree) - && SSA_NAME_RANGE_INFO (phi_result)) + && SSA_NAME_RANGE_INFO (phi_result) + && gimple_bb (SSA_NAME_DEF_STMT (new_tree)) == cond_block + && dbg_cnt (phiopt_edge_range)) duplicate_ssa_name_range_info (new_tree, SSA_NAME_RANGE_TYPE (phi_result), SSA_NAME_RANGE_INFO (phi_result)); |